1. Technical Field
The present invention relates to an image forming apparatus capable of controlling a nozzle group used to form an image on an image forming medium on the basis of image data.
2. Related Art
There are known line ink jet printers that include a head row ejecting ink to the entire one line of a sheet in a width direction of the sheet and perform printing in the width direction of the sheet without movement of heads. In some line ink jet printers, a plurality of head rows is arranged in a transport direction of a sheet to realize, a high-quality image and multiple colors, for example.
In the line ink jet printers, for example, the head row is constituted by a plurality of heads and a plurality of head controllers each controlling a head (a nozzle group formed by each head) is provided. In the line ink jet printers, for example, image data received from a PC (Personal Computer) are required to be transmitted to the plurality of head controllers.
For example, in order for distribution units formed on one board to transmit the image data to the plurality of head controllers, a plurality of data output ports (slots) of the head controllers has to be disposed on the board. In this case, it is difficult to physically realize this structure since numerous wirings are disposed on the board. Moreover, a problem may arise in that noise is increased.
In order to solve this problem, a line ink jet printer has been suggested which includes a plurality of distribution units connectable to a plurality of head controllers, which transmits image data to the plurality of distribution units from a PC, and which transmits the image data to the head controllers connected to the distribution units. In this case, the PC has to transmit the image data to the plurality of distribution units.
For example, a data communication technique used when a plurality of units (apparatuses) exist is disclosed in JP-A-5-173991 and JP-A-6-266683.
In the line ink jet printers, it is necessary to transmit image data from the PC at a high speed. Therefore, in order to transmit the image data to the plurality of distribution units, output ports (slots) for high-speed data transmission have to be disposed in the PC. For this reason, a problem may arise in that the cost is increased. Moreover, only a limited number of output ports for the high-speed data transmission is formed in the PC. Therefore, in some cases, a number of distribution units may not be dealt with.